Expedited Partner Therapy (EPT) has been shown to reduce rates of persistent or recurrent gonorrhea and chlamydia infection in heterosexual patients, but has not been evaluated for use among men who have sex with men (MSM). CDC guidelines support the use of EPT for partner management with heterosexual patients, but note the absence of evidence necessary to make an equivalent recommendation for the use of EPT with MSM. Randomized clinical trials to assess the impact of EPT on partner notification, treatment, and STI re- infection among MSM are critical to the development of evidence-based partner management guidelines. Our recent data from urban Peru has identified prevalences of rectal and pharyngeal gonorrhea and chlamydia ranging from 5-20%. The elevated burden of disease among MSM in Peru suggests that frequent transmission of undiagnosed gonorrhea and chlamydia through MSM sexual networks may be a factor contributing to the persistently high incidence of HIV infection among MSM in the region. We propose a pilot evaluation of the effect of EPT on partner notification and treatment among MSM in Peru diagnosed with gonorrhea or chlamydia at any anatomic site. Specific Aim 1: To explore the social norms and structural factors influencing partner notification and treatment among MSM in Peru. Specific Aim 2: To determine the effect of EPT on anticipated and actual partner notification among MSM diagnosed with gonorrhea or chlamydia infection. Specific Aim 3: To develop preliminary data on rates of gonococcal and chlamydial re-infection among MSM randomized to receive EPT compared with standard partner notification counseling. As a theoretical model, EPT integrates behavioral, social, and biomedical approaches to HIV/STI control in a comprehensive prevention intervention. Our proposed exploration of the social and behavioral dimensions of partner notification and treatment will provide a methodological structure for understanding the influence of EPT on behavioral decision-making processes, interpersonal factors that influence partner notification, and network patterns of STI transmission within MSM populations in Peru. Our biomedical assessment of gonorrhea and chlamydia re-infection will provide preliminary data to support the development of a definitive clinical trial of EPT for HIV/STI control in MSM populations. Practical issues including an evaluation of methods to assess notification and treatment rates, determination of the composition of participants'sexual networks (including the number of unlocatable partners in participant networks), and an overview of logistical issues involved in implementing and assessing an EPT intervention in the local environment, will all contribute to the development and refinement of a future trial of EPT for HIV/STI control with MSM. PUBLIC HEALTH RELEVANCE: STI co-infection is an important risk factor for HIV transmission during sexual intercourse, particularly among men who have sex with men (MSM). Expedited Partner Therapy (EPT) has been shown to be effective in controlling the spread of STIs in heterosexual partnerships, but has not been evaluated among MSM. We propose a pilot study of the impact of EPT on partner notification and treatment among MSM in Peru diagnosed with gonorrhea or chlamydia.